微型计算机在供热计量中的应用

本文就电厂供计量系统的组成做一简单介绍，主要介绍系统的软件设计特点及其实现方法。     

AlGaAs:Si中与DX中心有关的光生电子陷阱特性研究(英文)

A new electron trap state SD was found by DLTS measurement under light illumination in Si doped A.lxGa1-xAs. This new trap energy level ESD is shallower than the DX center energy in the gap and the concentration of SD is comparable to that of DX centers. The emission activation energy Ec=0.20±0.05eV and capture activation energy Ec= 0.17±0.05eV. The SD DLTS peak has never been detected previously because under dark and thermal equilibrium condition most of the electrons occupy the deeper DX states and most of SD states are empty. However, when the sample is illuminated by light, electrons are excited to the conduction band and then re-captured by SD since the deeper DX states have a slower electron capture rate, thus a new DLTS peak corresponding to SD appears. Constant temperature capacitance transient C-t and transient C-V measurements were also used to further confirm the existence of SD states.     

MBE MD AlGaAs/GaAs调制反射谱及其与2DEG浓度的关系(英文)

The two-dimensional electron gas concentration dependence of photore-flectance of n-AlGaAs/GaAs heterostructures is reported and explained by analysing the physical process induced by photo-modulation. Comparison of the experimental results and energy level calculations based on a triangular potential well approximation shows good agreement.     

瞬态C-V法测量AlGaAs:Si中DX中心的电离能(英文)

The thermal ionization energy ET of DX centers in AlxGa1-xAs and its dependence with the value of x and the pressure are very important for estab- lishing the model of DX centers. The conventional DLTS and Hall methods used to DX center measurement have some ambiguities in theoretical analysis and experiments and the values of ET determined are different with those methods. The new constant temperature transient C-V measurement is based on the fact that at low temperature both electron capture and emission rates of DX centers are very slow. During the transient C-V measurement, change; of bias voltages and capacitance measurements are completed in a time duration much shorter than the electron capture and emission time constants, therefore the electrons occupied on the DX centers are considered to be frozen. The density of DX centers, the distribution profile of electrons on DX centers in the depletion region of a Schottky diode at a constant reverse bias, and the density of free electrons in conduction band in the bulk and their temperature dependence have been measured.     

引江补汉工程实施后的 南水北调中线水源工程可调水量分析

随着新时期南水北调后续工程的高质量发展，首批建设工程引江补汉工程正式开工，为支撑未来南水北调 中线水源工程与引江补汉工程的联合协调运行，根据引江补汉工程设计参数，提出多组丹江口水库与引江补汉工 程联合调度方式，并模拟分析得到引江补汉工程实施后南水北调中线水源工程可调水量具有重要意义。研究结 果表明：设置引江补汉工程补水水位控制线、同步优化陶岔渠首引水调度线，充分利用引江补汉工程补水来满足 汉江中下游用水需求，从而置换更多坝前水量引至陶岔渠首、清泉沟等用水需求方，可在一定程度上实现丹江口 水库供水与引江补汉工程补水决策的有效衔接；相比于中线一期工程现状供水调度情景，采用合适的引江补汉工 程与中线水源工程联合调度方式，可在保障汉江中下游用水量需求的同时，满足下游断面最小用水量达标率至 98.9%~99.2%，并提高中线受水区可供水量 17.7 亿~25.8 亿 m3，继而有效协调中线水源工程的中线受水区、清泉沟 渠首及汉江中下游等多方用水需求。     

幼儿电子成长档案制作初探

幼儿成长档案是反映幼儿学习与发展状况的资料，是对幼儿成长过程的评价和记录。《幼儿园教育指导纲要》中指出，对幼儿的评价应是一个动态评价，是一个持续的过程，它对幼儿发展的分析包含了过去、现在和未来。为每位幼儿建立成长档案能为教师因材施教提供依据；为幼儿提供自我展示的舞台；让家长更加了解自己的孩子；也为幼儿留下美好的回忆。     

如何选择集散控制系统

介绍了一种定量比较不同集散控制系统优劣的方法－－矩阵法，并详细阐述了其使用方法。     

Al_xGa_(1-x)As-GaAs多层量子阱结构的流体静压光荧光研究

本文对Al_xGa_(1-x)As-GaAs多层量子阱结构的子带间跃迁能的压力关系做了77K低温下的光荧光光谱研究.实验结果表明,未掺杂的量子阱的非本征发光主要来自缺陷的束缚激子d~ox.d~ox束缚激子态在量子阱中的压力系数(5meV/kbar)与体材料中的压力系数(2.7meV/kbar)的比较表明,在量子阱中深中心发生了浅化.通过对不同子带间跃迁能的压力关系测量给出了GaAs Γ谷相应能量点的压力系数,结果表明Γ谷并不是以同一压力系数移动的刚性球.最后测量了量子阱的发光强度随压力的变化.